BILLINGS — Hunters killed at least nine infected deer during a pair of special hunts intended to gauge the prevalence of a newly-found wildlife disease in Montana, state officials said Friday.

The infected animals were among more than 450 deer killed during the hunts in Carbon and Liberty counties, which were held in response to the appearance last fall of chronic wasting disease. The fatal neurological illness is endemic in surrounding states and provinces and affects deer, elk and moose.

Eight of the nine infections found to date in Montana were shot in Carbon County. Tests still are pending on some animals killed in the special hunts. Results are expected to be available in about two weeks.

State officials hope to keep the prevalence rate below 5 percent of animals in any given population, said Montana Fish, Wildlife and Parks spokesman Greg Lemon. On Thursday, wildlife commissioners approved maximum quotas of up to 5,000 deer, 1,000 elk and 20 moose that could be killed during special hunts over the next two years.

The disease has been found in 25 states and efforts to eradicate or at least manage it have had limited success, said Bryan Richards, chronic wasting disease project leader for the U.S. Geological Survey.

“Our experience tells us it’s not going to go away. It’s likely to get a good foothold and be established,” Richards said. “We don’t a have a good tool set for managing this disease.”

It’s uncertain what additional steps will be taken next to keep chronic wasting from spreading in Montana. One measure already in place is a restriction on transporting certain parts of deer killed in Carbon County to anyplace other than Carbon and Yellowstone counties.

There have been no cases of humans being sickened by exposure to the disease, but health officials recommend not consuming meat from infected animals as a precaution.